I used to think Lovelock was way off base too, but now I am afraid he could be correct. If you follow the following...

The British publication New Scientist contrasted the scientific imperative regarding GHG emissions with stated policy goals, citing research by Andrew Weaver of University of Victoria, Canada. “They modelled the reduction of industrial emissions below 2006 levels by between 20% and 100% by 2050. Only when emissions were entirely eliminated did the temperature increase remain below 2°C.” By contrast “The European Union nations have agreed to limit their emissions to 20% below 1990 levels by 2020, and support dropping global emissions to 50% below 1990 levels by 2050.” So we have this bizarre situation where governments agree not to exceed 2C, and yet make emissions policies that lead to exceeding that threshold.
http://environment.newscientist.com/article/dn12775-zero-emissions-neede...

But even this 100% is apparently not enough....

The loss of ice in the Arctic was unprecedented this summer. The implications are summarized in a report titled The Big Melt by a United Kingdom organization named Carbon Equity. They have a very thorough web site and the report does an excellent job of explaining why climate models have underestimated the rate of climate change. In summary, climate models are good at representing “fast feedbacks” but don’t include “slow feedbacks.” A politically generated policy has been in place to find the emissions rate that will stabilize GHG to give a 50/50 chance the planet will not go above 2C global average. This is why you often here about a 450 ppm CO2 equivalent target. However, this is far too high when “slow feedbacks” such as loss of carbon sinks and decay of permafrost and peat are included. Furthermore, it looks like modeling of ice sheet dynamics and the rate of sea level rise needs to be reassessed given current conditions in the Arctic and Greenland. Probably the most disturbing set of information I have absorbed in a very long while.
http://energybulletin.net/35843.html

Biologist and Australian of the year, Tim Flannery was quoted as saying that the next IPCC report will conclude that we have already passed the 450 ppm CO2 equivalent. The excellent blog run by professional climatologists Real Climate had a critique of the specifics of Flannery’s claims (http://www.realclimate.org/index.php/archives/2007/10/co2-equivalents/) but given the points raised by The Big Melt, these critiques are likely beside the point. See discussion here:
http://www.energybulletin.net/35883.html